I have some gasoline (20:1) oil mix for my (2 stroke) snow blower.
I mixed 2 gallons of it 3 years ago now.
I have been using it the last 2 seasons.
Is it still good to use?
The snowblower seems to like it.
The oil, did have a fuel stabilizer in it.
The El Cerrito Fire Department says the shelf life of gasoline is 6 months.
Another site has a discussion of gasoline relating to outboard motors that get only seasonal use.
I always thought it was 6 months myself.
I used the two year old gas with no issues last year.
I guess I will try the 3 year vintage this season and see how it goes. 